Retirement Plans - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2014 Directors
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Number of director eligible for the benefit under defined benefit plan	3
Directors' Retirement Plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Annual retirement benefit age	75 years
SERP [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Annual retirement benefit age	65 years
Annual retirement benefit percentage	25.00%
Credited service	1 year
Number of payments	Lump sum or ten equal annual payments
Credited service description	Twenty or more years
Benefit plan premium equally paid	10 years
Benefit payable upon early retirement	At age 50 with at least twelve years of service
Service needed to lesser benefit payable upon early retirement	12 years
Minimum [Member] | ESB Financial Corporation Director's Retirement Plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service period to get retirement benefit	5 years
Retirement benefit calculation ratio	25.00%
Years of service required for ratios	10 years
Minimum [Member] | SERP [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Final average pay multiplied by a ratio	1.25%
Participants credited service under benefit plans	23 years
Maximum [Member] | ESB Financial Corporation Director's Retirement Plan [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Service period to get retirement benefit	10 years
Retirement benefit calculation ratio	80.00%
Years of service required for ratios	20 years
Maximum [Member] | SERP [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Final average pay multiplied by a ratio	25.00%
Participants credited service under benefit plans	35 years